I would like to mention for all those interested in 3D printing that the
schematics for a few types of 3D printers are freely available at the
link below. The most noteworthy thing about the RepRap project is that
the designs are open source and can be assembled for about $700 or
possibly less, unlike the $10,000+ that most companies charge for
commercial models. These are also designed to use as many plastic parts
as possible so that the majority of a printer can be quickly created
using other 3D printers. The video on the web site explains it more
thoroughly.
http://reprap.org/